textproduct: Rapid City

KEY MESSAGES

-Isolated storms possible in the far west Wed afternoon

-Isolated to scattered severe storms possible over the Black Hills and southeast Thur afternoon

-Near normal temperatures continue through Thursday, then warming for the weekend

UPDATE

Issued at 926 PM MDT Tue Aug 25 2026

General NW flow aloft will persist through the end of the week. Main impusle track will remain south of the FA Wed as another round of isolated shra and TS are expected to push SE across WY, possibly clipping the far SW FA. Deeper moisture will shift back into the FA Thur per LL SE flow, as the mid level impulse track shifts north. This will support a good chance of TS from the BH southeast into SW SD as storms fire on the Hills in the afternoon per weak CIN. Deep layer shear will be more than sufficient for a couple supercells, supporting a large hail threat on the BH and adjacent Plains, with damaging winds on the adjacent Plains. Have increased pops and spread chances from the BH SE to the Nebraska border. Warm and dry Friday and most of Sat. Next chance of rain still looks to be Sat night into Sunday, best chances across NW SD.

DISCUSSION

(This Evening Through Tuesday) Issued at 1248 PM MDT Tue Aug 25 2026

Northwest flow continues over the forecast area, as upper ridge sits over the western CONUS. 18Z surface analysis shows high pressure centered over Montana this afternoon, while a frontal boundary sits to our south in Nebraska. Winds are currently breezy out of the northwest with temperatures in the upper 70s and 80s. Current radar has some light returns over south central SD and northeastern WY.

Isolated storms/showers will be possible this afternoon and early evening, however lack of any CAPE and shear should keep any storms sub-severe. Similar setup for Wednesday, with isolated sub-severe storms possible in the lower half of the forecast area. Upper ridge transitions over the northern and central plains on Friday, prompting a warming trend back into the 90s for the weekend. Next disturbance to affect the region moves through on Saturday, however the better forcing currently looks like it will stay mostly north of our region, though still may clip northwestern into central SD.

By Sunday, the upper ridge slides eastward, and southwest flow sets up aloft. Temperatures cool back to near normal for early next week. Multiple weak disturbances will prompt near daily chances for isolated showers and storms in the area. Longer range models show possibly stronger wave moving through the region next Wednesday, but will have to monitor as we move into next week.

AVIATION

(For the 06Z TAFS Through 06Z Wednesday Night) Issued At 1035 PM MDT Tue Aug 25 2026

VFR conditions are expected through the forecast period. Isolated showers and thunderstorms will be possible Wednesday afternoon and evening across NE WY and SW SD.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.